Field of the Invention
The present invention is directed generally to communications connectors, and more particularly to registered jack 45 (“RJ-45”) type connectors.
Description of the Related Art
Standards committees are in the process of developing specifications for a Next Generation (“Next Gen”) Data Transmission System that will provide data rates of approximately 40 gigabit per second (sometimes abbreviated as “40G”) over a distance of approximately 40 meters using twisted pair copper cables. The system will consist of electronic transceiver devices and structured cabling. Requirements for the transceiver devices will be specified by one standards committee while the structured cabling requirements will be specified by others. The standards committees involved coordinate with each other during the standards development process to provide a reliable, cost effective transmission system.
The structured cabling connects between two of the transceivers and is used as the medium to carry data back and forth between the two devices. Structured cabling consists of cable, patch cordage and connectors which will be interconnected to form channels. It is likely that Next Gen channels will consist of a maximum number of two, and possibly less, connector interfaces. Each connector interface consists generally of an outlet (sometimes referred to as a “jack”) and a plug. Thus the channels and their components, along with the electronic transceivers, must be configured to work together to be able to deliver the specified data through-put up to the specified distance.
This application discloses structured cabling, more specifically, the connectors used in a structured cabling system. The specification and operation of the electronic transceiver devices that may be used in association with the connectors and structured cabling disclosed in this application are understood by those of ordinary skill in the art to be used pursuant to specifications ensuring the individual components of such a system work together to deliver the desired overall system performance.
Such a system will likely operate over a frequency range of up to about 2 gigahertz (“GHz”). Some key requirements for the structured cabling portion of the system (also referred to as “channels”) will include return loss (“RL”), insertion loss (“IL”), near end crosstalk (“NEXT”) and power sum alien crosstalk (“PSANEXT”). Components of the channel (e.g. cable, patch cordage and connectors) will each have corresponding requirements for these key parameters as well as a considerable number of other specified parameters. It is likely that the nomenclature used to refer to the Next Gen of cabling will be “Category 8” which is in line with the naming of its predecessors (e.g., Categories 1, 2, 3, 4, 5, 5e, 6, and 6A).
Next Gen cabling will likely include cables and patch cordage similar to existing Category 6A unshielded twisted pair (“UTP”) cables and patch cordage, however, their designs will be modified somewhat to enable them to meet the electrical requirements for Next Gen. It is likely that an overall shield will be added to enable the cables and patch cordage to meet the PSANEXT requirements specified for Next Gen cables.
Similarly Next Gen cabling will likely include RJ-45 type connectors (outlets and plugs) that are similar to existing Category 6A connectors, however, their designs will be modified somewhat to enable them to meet the electrical requirements for Next Gen. As with the cables, it is likely that an overall shield will be added to the plug and outlets to enable them to meet the PSANEXT requirements specific for Next Gen connectors.
One standards committee, the Telecommunication Industry Association (“TIA”) TR-42.7 subcommittee, is considering enhancing the performance of RJ-45 type connectors such that they will meet all the electrical requirements for the Next Gen standard up to the highest frequencies specified. RJ-45 type connectors include a plug and an outlet configured to be connected together to form a mated connection or mated connector.
It is interesting to note that when RJ-45 connector technology was first developed in the mid 1970's at operating frequencies for use with voice transmissions in telephone technologies, it was thought that someday RJ-45 connectors may be used for operating frequencies of up to about 2 megahertz (“MHz”), which is 1000 times less than the operating frequency (2 GHz) required by the Next Gen standard.
RJ-45 type connectors have some inherent transmission performance issues, the root of which lies in the geometry of the spade contacts used in the plug and the manner in which these contacts are assigned to specific conductors of specific pairs. The plug's geometry creates substantial levels of transmission impairment in the form of crosstalk and, to a lesser extent, RL. Over the years, despite increased performance demands on the RJ-45 technology, engineers have managed to overcome these performance issues caused by the plug through the application of certain compensation schemes and transmission enhancing techniques in the outlet. Such designs enable the industry to continue to use the same general form factor of plug and outlet and maintain the mechanically and electrically backwards compatibility of new product to existing product.
Other types of connector technology have also been proposed but are mechanically incompatible with the RJ-45 type connector form factor. Given the general low cost of RJ-45 technology, and its wide spread proliferation over the years, the industry has generally stayed with the RJ-45 type connector for transmission speeds up to, and including, 10 gigabits per second (“10G”). Now, however, as the industry begins to look to 40 gigabits per second transmission rates using copper cabling, some question the ability of the RJ-45 type connector to perform well enough for Next Gen applications.
To date, at least one manufacturer has proposed a design that enables RJ-45 type connectors to perform at up to about 2 GHz. This design uses some unique electrical techniques in the plug to accomplish compensation at higher frequencies. Such solutions, however, though largely backwards compatible with existing product, still have the same inherent transmission performance issues of the original plug. To date, results have shown fair performance but, in order to be effective, the plug has so far been used solely with just one manufacturer's proprietary outlet which utilizes a unique tine design.
Therefore, a need exists for new connectors configured to perform in accordance with new standards (e.g., the Next Gen or Category 8 standard) but maintain backwards compatibility with connectors constructed pursuant to other standards (e.g., Categories 1, 2, 3, 4, 5, 5e, 6 and 6A). In addition, it would be desirable that the design of any such connector be more universally compatible with existing outlet designs and the tine structures that manufacturers typically employ. The present application provides these and other advantages as will be apparent from the following detailed description and accompanying figures.